Re: flying with a 3mo old?
The hotel should have pack n plays to rent you--call and check, and bring your own sheets for it.
I flew from LAX to Australia on my own with my baby when he was that age and it was easy as. Don't know how long your flight is, but you can have a flight attendant hold your baby (or your seat mate if they're willing) if you need to use the bathroom, too.
Mama to boy 1
(04/06) and boy 2
and boy 3